Plessey buys Cambridge LED startup
Plessey has bought Cambridge University spin-out CamGaN to commercialise new technologies for the growth of gallium nitride (GaN) high-brightness LEDs on large silicon substrates. The acquisition will enable Plessey to exploit synergies with its 6-inch processing facility in Plymouth to produce high brightness LEDs, and position it among the first commercial players to successfully manufacture HB LEDs on 6-inch silicon substrates.
The move parallels the acquisition of University of Bath spin-out NanoGaN by IQE in October 2009, although IQE only supplies the wafers for such HB LEDs. Plessey’s advantage is adding its existing design technology alongside to created integrated sensor and lighting systems.
The newly acquired Plessey HB LED solution enables the growth of thin HB LED structures on standard, readily
available, silicon substrates. Current technologies use silicon carbide (SiC) or sapphire substrates, which are
expensive and difficult to scale-up. Plessey’s GaN-on-silicon solution offers cost reductions of the order of 80%
compared to LEDs grown on SiC or sapphire by reducing scrap rates, minimising batch time and enabling
the use of automated semiconductor processing equipment. These cost reductions will be achieved while enabling
outputs in excess of 150 lumens per watt later this year – a combination that will allow Plessey to offer the most cost effective solutions in the HB LED industry.
“HB LED lighting represents the future of domestic, architectural, medical and automotive lighting,” said Michael LeGoff, Plessey’s Managing Director. “Achieving the goals of high efficiency and brightness is key to the rapid
deployment of energy saving, solid state lighting. This new British technology provides cost and performance
advantages that will constitute a game-changing step forward towards the replacement of incandescent and
fluorescent bulbs with HB LED lamps.”
“To date, the biggest technological challenge preventing the commercialisation of HB LEDs grown on large-area silicon substrates has been the large lattice mismatch between GaN and silicon. Plessey’s new GaN-on-silicon process has overcome this challenge and our expertise combined with the intrinsic cost savings of using automated 6 inch processing equipment will position Plessey’s HB LED lighting products at the forefront of the industry,” said Dr John Ellis, Chief Engineer at Plessey.
Plessey is also looking to release a range of products for smart lighting concepts that incorporate existing
Plessey sensing and control technologies including the award winning EPIC sensor. These smart lighting products will enable intelligent energy management, remote control, controlled dimming and automated response to ambient conditions.
Plessey’s first samples of a blue LED are characterised by peak emission at 460nm. The technology extends to other emission wavelengths such as cyan and green. Being able to achieve such high brightness at the blue end of the spectrum enables phosphors to be used to produce white light with a balanced spectrum of light emission that is better for the eye. White output powers of 150 lumens/watt are planned for late Q4 2012.